<!DOCTYPE html>   
<html>   
<head>   
    <meta charset="UTF-8">   
    <title>HTML5模拟微信聊天界面</title>   
    <style>   
  /**重置标签默认样式*/    
        * {    
            margin: 0;    
            padding: 0;    
            list-style: none;    
            font-family: '微软雅黑'    
        }    
        #container {    
            width: 450px;    
            height: 780px;    
            background: #eee;    
            margin: 80px auto 0;    
            position: relative;    
            box-shadow: 20px 20px 55px #777;    
        }    
        .header {    
            background: #000;    
            height: 40px;    
            color: #fff;    
            line-height: 34px;    
            font-size: 20px;    
            padding: 0 10px;    
        }    
        .footer {    
            width: 430px;    
            height: 50px;    
            background: #666;    
            position: absolute;    
            bottom: 0;    
            padding: 10px;    
        }    
        .footer input {    
            width: 275px;    
            height: 45px;    
            outline: none;    
            font-size: 20px;    
            text-indent: 10px;    
            position: absolute;    
            border-radius: 6px;    
            right: 80px;    
        }    
        .footer span {    
            display: inline-block;    
            width: 62px;    
            height: 48px;    
            background: #ccc;    
            font-weight: 900;    
            line-height: 45px;    
            cursor: pointer;    
            text-align: center;    
            position: absolute;    
            right: 10px;    
            border-radius: 6px;    
        }    
        .footer span:hover {    
            color: #fff;    
            background: #999;    
        }    
        #user_face_icon {    
            display: inline-block;    
            background: red;    
            width: 60px;    
            height: 60px;    
            border-radius: 30px;    
            position: absolute;    
            bottom: 6px;    
            left: 14px;    
            cursor: pointer;    
            overflow: hidden;    
        }    
        img {    
            width: 60px;    
            height: 60px;    
        }    
        .content {    
            font-size: 20px;    
            width: 435px;    
            height: 662px;    
            overflow: auto;    
            padding: 5px;    
        }    
        .content li {    
            margin-top: 10px;    
            padding-left: 10px;    
            width: 412px;    
            display: block;    
            clear: both;    
            overflow: hidden;    
        }    
        .content li img {    
            float: left;    
        }    
        .content li span{    
            background: #7cfc00;    
            padding: 10px;    
            border-radius: 10px;    
            float: left;    
            margin: 6px 10px 0 10px;    
            max-width: 310px;    
            border: 1px solid #ccc;    
            box-shadow: 0 0 3px #ccc;    
        }    
        .content li img.imgleft {     
            float: left;     
        }    
        .content li img.imgright {     
            float: right;     
        }    
        .content li span.spanleft {     
            float: left;    
            background: #fff;    
        }    
        .content li span.spanright {     
            float: right;    
            background: #7cfc00;    
        }    
    </style>   
    <script>   
        window.onload = function(){    
            var arrIcon = ['http://www.xttblog.com/icons/favicon.ico','http://www.xttblog.com/wp-content/uploads/2016/03/123.png'];    
            var num = 0;     //控制头像改变    
            var iNow = -1;    //用来累加改变左右浮动    
            var icon = document.getElementById('user_face_icon').getElementsByTagName('img');    
            var btn = document.getElementById('btn');    
            var text = document.getElementById('text');    
            var content = document.getElementsByTagName('ul')[0];    
            var img = content.getElementsByTagName('img');    
            var span = content.getElementsByTagName('span');    
   
            icon[0].onclick = function(){    
                if(num==0){    
                    this.src = arrIcon[1];    
                    num = 1;    
                }else if(num==1){    
                    this.src = arrIcon[0];    
                    num = 0;    
                }                    
            }    
            btn.onclick = function(){    
                if(text.value ==''){    
                    alert('不能发送空消息');    
                }else {    
                    content.innerHTML += '<li><img src="'+arrIcon[num]+'"><span>'+text.value+'</span></li>';    
                    iNow++;    
                    if(num==0){    
                        img[iNow].className += 'imgright';    
                        span[iNow].className += 'spanright';    
                    }else {    
                        img[iNow].className += 'imgleft';    
                        span[iNow].className += 'spanleft';    
                    }    
                    text.value = '';    
     // 内容过多时,将滚动条放置到最底端    
     contentcontent.scrollTop=content.scrollHeight;      
                }    
            }    
        }    
    </script>   
</head>   
<body>   
    <div id="container">   
        <div class="header">   
            <span style="float: left;">业余草:模拟微信聊天界面</span>   
            <span style="float: right;">14:21</span>   
        </div>   
        <ul class="content">   
   <!-- 欢迎加入qq群：454796847、135430763 -->   
  </ul>   
        <div class="footer">   
            <div id="user_face_icon">   
                <img src="http://www.xttblog.com/icons/favicon.ico" alt="">   
            </div>   
            <input id="text" type="text" placeholder="说点什么吧...">   
            <span id="btn">发送</span>   
        </div>   
    </div>   
</body>   
</html>   
